The results of examination of 60 patients presenting with chronic diffuse disorders of the liver and seventy experimental animals with toxic affection of the liver, having been administered spirulina treatments, suggest clinical-and-laboratory effectiveness of this drug. The hepatoprotective properties of spirulina are referrable to its antiinflammatory, antioxidant, membrane-stabilizing, and immunocorrecting actions. In this way the employment of spirulina is believed to be pathogenetically validated in chronic diffuse liver conditions, permitting stabilizing the process and preventing the transformation of chronic hepatitis into hepatocirrhosis.